Green vegetable discoloration and fading inhibitor

Abstract

To provide a green vegetable discoloration and fading inhibitor, and foods containing the green vegetable discoloration and fading inhibitor.SOLUTION: A green vegetable discoloration and fading inhibitor contains vinegar, magnesium phosphate, cyclodextrin, reducing sugar, ascorbic acid and salts thereof, and sodium chloride, where the pH of the solution is controlled to 5.0 or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an agent for preventing discoloration and fading of green vegetables. [Background technology]

[0002] Green vegetables are in high demand not only for their vivid appearance, but also for their taste and high nutritional value. Green vegetables are not only eaten as salads, but are often processed by various cooking methods such as heating and soaking in seasoning liquids. Among them, pickles and pickled vegetables, which are made by soaking vegetables in seasoning liquids containing salt and vinegar, are in high demand because of their expected health benefits, good preservation properties, and good taste. However, many pickles and pickled vegetables have an acidic pH (pH 5.0 or less) to suppress the growth of microorganisms (Non-Patent Document 1), which is the pH range in which the chlorophyll contained in green vegetables decomposes and discolors (Non-Patent Document 2). It is also known that chlorophyll decomposes under light exposure and temperature. Therefore, when green vegetables are processed into pickles or pickled vegetables, synthetic colorants such as tar dyes are sometimes used because they discolor due to pH and light, but since it is not possible to completely maintain the vivid green color and there are problems such as health effects, various technologies have been proposed to preserve the chlorophyll contained in vegetables.

[0003] Patent Document 1 discloses a technique for stabilizing chlorophyll using L-ascorbic acid and trimagnesium phosphate as active ingredients. However, this method requires the use of a large amount of L-ascorbic acid to dissolve trimagnesium phosphate, and there are problems with the addition of ascorbic acid, such as its effect on taste and cost.

[0004] Patent Document 2 discloses a quality preservation agent that contains a magnesium-containing compound, ascorbic acid and / or its salt, and α-lipoic acid and / or its complex, and stabilizes chlorophyll in an aqueous solution having a pH of 7.5 to 9.5, as a method for supplying magnesium. However, this method has a pH range of 7.5 to 9.5, and is not suitable for use with foods with an acidic pH (particularly pH 5.0 or less).

[0005] Patent Document 3 discloses a fruit and vegetable preservative in which fruit and vegetables are immersed in a solution containing magnesium ions, zinc ions, or tin ions and ascorbate ions or erythorbate ions. However, this method has problems such as the health effects of excessive intake of tin or zinc.

[0006] Patent Document 4 discloses a technique for stabilizing chlorophyll using dimagnesium phosphate as an active ingredient. However, this method does not exhibit the effect of preventing discoloration when used at a pH of less than 5.0. [Prior art documents]

[0007] [Patent Document 1] Patent Publication No. 2022-50468 [Patent Document 2] Patent Publication No. 11-196764 [Patent Document 3] Patent 4583169 [Patent Document 4] Patent Publication No. 7-46972 [Non-Patent Document 1] Lahellec, C. et al.: Growth effect of sorbate and selected antioxidants on toxigenic strains of Staphylococcus aureus.J.Food Prot.Vol.44,pp531-534 [Non-Patent Document 2] Yasunori Mori, Kumiko Kita, Setsuko Miyazaki, Study on the Stability of Chlorophyll, Home Economics Journal, 1964, Vol. 15, No. 1, p. 2 Summary of the Invention [Problem to be solved by the invention]

[0008] Such conventional technology had problems such as the addition of other metal salts or active ingredients, which affected taste, health, and costs, and the inability to use at low pH (particularly pH 5.0 or lower).In light of this background, there was a need for an agent to prevent discoloration and fading of green vegetables that could be used at a pH (particularly 5.0 or lower) where bacterial growth is suppressed and that did not adversely affect taste, health, or costs. [Means for solving the problem]

[0009] The agent for preventing discoloration and fading of green vegetables of the present invention is characterized in that it contains, in addition to vinegar and magnesium phosphate, one or more members selected from the group consisting of cyclodextrin, reducing sugar, ascorbic acid and its salts, and sodium chloride. Effect of the Invention

[0010] The present invention has little effect on the taste quality of food and makes it possible to prevent discoloration and fading of green vegetables even at pH 5.0 or below, at which point chlorophyll is easily decomposed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The agent for preventing discoloration and fading of green vegetables used in the present invention contains vinegar, magnesium phosphate, and one or more selected from the group consisting of cyclodextrin, reducing sugar, ascorbic acid and its salts, and sodium chloride, and the amounts of each combination added are such that the mixing ratio when made into a solution is 20 to 40 mass% vinegar, 0.1 to 5 mass% magnesium phosphate, 0.1 to 5 mass% cyclodextrin, 0.1 to 25 mass% reducing sugar, 0.1 to 10 mass% ascorbic acid and its salts, and 0.1 to 2 mass% sodium chloride, preferably The discoloration and fading prevention agent for green vegetables is characterized by having a pH adjusted to 5.0 or less and is composed of 30 to 35 mass% vinegar, 1 to 3 mass% magnesium phosphate, 0.5 to 1.5 mass% cyclodextrin, 1 to 20 mass% reducing sugar, 1 to 3 mass% ascorbic acid and its salts, and 0.5 to 1.5 mass% sodium chloride, more preferably 33.3 mass% vinegar, 2 mass% magnesium phosphate, 1 mass% cyclodextrin, 10 mass% reducing sugar, 2 mass% ascorbic acid and its salts, and 1 mass% sodium chloride.

[0012] The vinegar used in the present invention may be synthetic vinegar, brewed vinegar, grain vinegar, rice vinegar, black rice vinegar, black barley vinegar, fruit vinegar, apple vinegar, grape vinegar, etc. These vinegars may also be adjusted by adding an organic acid or a salt thereof, for example, acetic acid, sodium acetate, citric acid, sodium citrate, malic acid, sodium malate, tartaric acid, sodium tartrate, succinic acid, sodium succinate, lactic acid, sodium lactate, etc.

[0013] Examples of the cyclodextrin used in the present invention include α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin, and among these, β-cyclodextrin is most preferred because of its excellent discoloration prevention effect.

[0014] The reducing sugar used in the present invention may be fructose, glucose, lactose, maltose, sorbitol, erythritol, reduced starch syrup, or the like.

[0015] As the ascorbic acid and its salts for use in the present invention, sodium ascorbate is most preferred.

[0016] The magnesium phosphate used in the present invention is most preferably trimagnesium phosphate.

[0017] The agent for preventing discoloration and fading of green vegetables of the present invention can use a pH adjuster, and examples of the pH adjuster that can be used include inorganic acids such as phosphoric acid, monosodium phosphate, monopotassium phosphate, disodium phosphate, dipotassium phosphate, trisodium phosphate, tripotassium phosphate, etc., or salts thereof, and organic acids such as citric acid, sodium citrate, etc., or salts thereof.

[0018] The present invention will be described in detail below with reference to experimental examples, but the present invention is not limited to these experimental examples.

[0019] Experimental Example 1 [Examples 1 to 36, Comparative Examples 1 to 17] Vinegar (Mizkan Grain Vinegar: Mizkan Co., Ltd.), trimagnesium phosphate, magnesium chloride, cyclodextrin (α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin), reducing sugar (sorbitol or fructose glucose liquid sugar (New Fract 55: Showa Sangyo Co., Ltd.)), and disodium hydrogen phosphate were dissolved in purified water in the ratios shown in Table 1. Spinach, broccoli, okra, and green beans were immersed in these solutions in a weight ratio of 1 vegetable to 2 solution in transparent nylon plastic bags (70 μm thick). After immersion, the opening of the bag was immediately heat-sealed and left to stand for 8 days under conditions of 5°C and 500 lux. The effects of preventing discoloration and fading on various vegetables were evaluated after 1 day, 2 days, 3 days, 5 days, and 8 days using the following method. <Evaluation criteria> ◎ Retains the bright green color of vegetables. ○ ···Retains the green color of vegetables. △: Retains some of the green color of vegetables. ×...It has turned brown. *After three days, vegetables that still retained some of their green color (evaluation standard: △) were judged to have the effect of preventing discoloration and fading, and vegetables that turned brown after three days were judged to have no effect of preventing discoloration and fading.

[0020] The results (Examples 1 to 36 and Comparative Examples 1 to 17) are shown in Table 1.

[0021] [Table 1]

[0022] As for the two-type combination, when vinegar was combined with any one of trimagnesium phosphate, magnesium chloride, cyclodextrin, and reducing sugar (sorbitol or New Fract 55) (Comparative Examples 2 to 17), the color changed to brown after three days, and it was determined that there was no discoloration prevention effect. The combination of 3% by mass of magnesium chloride (Comparative Example 3) slightly retained the green color after one day, while the combination of 2% by mass of trimagnesium phosphate (Comparative Example 2) retained the green color after one day. This shows that trimagnesium phosphate is more effective at retaining the green color than magnesium chloride. Therefore, trimagnesium phosphate was used when examining combinations of three or more types.

[0023] Of the three combinations, when vinegar, trimagnesium phosphate, and cyclodextrin or reducing sugar were combined (Examples 1 to 24), the green color was not browned even after three days, and was maintained or slightly maintained, and therefore it was determined that there was a discoloration prevention effect. The combination of 33.3% by mass vinegar, 2% by mass trimagnesium phosphate, and 1% by mass β-cyclodextrin (Example 2) and the combination of 33.3% by mass vinegar, 2% by mass trimagnesium phosphate, and 10% by mass reducing sugar (Examples 7 to 8) maintained their green color even after three days, and showed the highest discoloration prevention effect among the three combinations.

[0024] Of the four combinations, when vinegar, trimagnesium phosphate, cyclodextrin, and reducing sugar were combined (Examples 25 to 36), the color did not turn brown even after three days, and the green color was maintained or slightly maintained, and therefore it was determined that there was a discoloration prevention effect. The combination of 33.3% by mass vinegar, 2% by mass trimagnesium phosphate, 1% by mass β-cyclodextrin, and 10% by mass reducing sugar (Examples 25 to 26) maintained the green color after five days and slightly after eight days, demonstrating the highest discoloration prevention effect among the four combinations.

[0025] Among the combinations that showed a discoloration prevention effect for 8 days under conditions of 5°C and 500 lux, those that showed a high discoloration prevention effect (Examples 25 to 26) were combined with sodium ascorbate and sodium chloride, and the light irradiation amount was increased from 500 lux to 1000 lux to evaluate in Experimental Example 2 whether discoloration of green vegetables could be prevented.

[0026] Experimental Example 2 [Examples 37 to 74] Vinegar (Mizkan Grain Vinegar: Mizkan Co., Ltd.), trimagnesium phosphate, cyclodextrin, reducing sugar (sorbitol or fructose glucose liquid sugar (New Fract 55: Showa Sangyo Co., Ltd.)), sodium ascorbate, and sodium chloride were dissolved in purified water in the ratios shown in Table 2. Spinach, broccoli, okra, and green beans were immersed in these solutions in a weight ratio of 1 vegetable to 2 solution in transparent nylon plastic bags (70 μm thick). After immersion, the opening of the bag was immediately heat-sealed and left to stand for 8 days under conditions of 5°C and 1000 lux. The effects of preventing discoloration and fading on various vegetables were evaluated after 1 day, 2 days, 3 days, 5 days, and 8 days using the following method. <Evaluation criteria> ◎ Retains the bright green color of vegetables. ○ ···Retains the green color of vegetables. △: Retains some of the green color of vegetables. ×...It has turned brown. *After three days, vegetables that still retained some of their green color (evaluation standard: △) were judged to have the effect of preventing discoloration and fading, and vegetables that turned brown after three days were judged to have no effect of preventing discoloration and fading.

[0027] The results (Examples 37 to 74) are shown in Table 2.

[0028] [Table 2]

[0029] Of the four combinations, when vinegar and trimagnesium phosphate were combined with any two of β-cyclodextrin, reducing sugar, sodium ascorbate, and sodium chloride (Examples 37 to 50), the green color was still somewhat maintained after eight days, and it was determined that there was an anti-discoloration effect. A combination of 33.3% by mass of vinegar, 2% by mass of trimagnesium phosphate, 1% by mass of β-cyclodextrin, and 10% by mass of reducing sugar (Examples 37-38), a combination of 33.3% by mass of vinegar, 2% by mass of trimagnesium phosphate, 1% by mass of β-cyclodextrin, and 2% by mass of sodium ascorbate (Example 39), a combination of 33.3% by mass of vinegar, 2% by mass of trimagnesium phosphate, 1% by mass of β-cyclodextrin, and 1% by mass of sodium chloride (Example 41), a combination of 33.3% by mass of vinegar, 2% by mass of trimagnesium phosphate, 10% by mass of reducing sugar, and 2% by mass of sodium ascorbate (Examples 43-44), and a combination of 33.3% by mass of vinegar, 2% by mass of trimagnesium phosphate, 10% by mass of reducing sugar, and 1% by mass of sodium chloride (Examples 47-48) maintained a green color after 5 days and slightly maintained a green color after 8 days, demonstrating a high discoloration prevention effect among the four combinations.

[0030] As for the five combinations, when vinegar and trimagnesium phosphate were combined with any three of β-cyclodextrin, reducing sugar, sodium ascorbate, and sodium chloride (Examples 51 to 70), the green color was maintained after five days and somewhat after eight days, so it was determined that there was an anti-discoloration effect.

[0031] Of the six combinations, the combination of vinegar, trimagnesium phosphate, β-cyclodextrin, reducing sugar, sodium ascorbate, and sodium chloride (Examples 71 to 74) maintained its green color even after eight days and was therefore deemed to have a discoloration prevention effect. The combination of 33.3% by mass of vinegar, 2% by mass of trimagnesium phosphate, 1% by mass of β-cyclodextrin, 2% by mass of sodium ascorbate, and 1% by mass of sodium chloride (Examples 71 to 72) maintained a vivid green color after five days and maintained its green color after eight days, demonstrating the highest discoloration prevention effect among the six combinations. [Industrial Applicability]

[0032] The present invention has little effect on taste and can be used for foods with a low pH, making it extremely useful for reducing food waste.

Claims

1. An agent for preventing discoloration and fading of green vegetables, which contains vinegar, magnesium phosphate, and reducing sugar.

2. An agent for preventing discoloration and fading of green vegetables, which contains vinegar, magnesium phosphate, and cyclodextrin.

3. 3. The agent for preventing discoloration and fading of green vegetables according to claim 2, further comprising a reducing sugar.

4. 4. The agent for preventing discoloration and fading of green vegetables according to claim 1, further comprising ascorbic acid or a salt thereof.

5. The agent for preventing discoloration and fading of green vegetables according to any one of claims 1 to 4, further comprising sodium chloride.

6. 6. The agent for preventing discoloration and fading of green vegetables according to claim 2, wherein the cyclodextrin is β-cyclodextrin.

7. 7. The agent for preventing discoloration and fading of green vegetables according to claim 4, wherein the ascorbic acid or a salt thereof is sodium ascorbate.

8. The agent for preventing discoloration and fading of green vegetables according to any one of claims 1 to 7, wherein the magnesium phosphate is trimagnesium phosphate.

9. The agent for preventing discoloration and fading of green vegetables according to any one of claims 1 to 8, which has a pH of 5.0 or less when made into a solution.

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